Interesting.  I live in Chicago, and although maybe not the mid-west, it is close to it.  :)

Actually, i can't say I have never seen a brick paved alley, just never a red brick paved alley.  I guess it is possible it was red brick when first paved, but usually it is a dark brown or even black brick.  Most of the alleys here are asphalt under all the dirt and crud.  Just my thoughts. 

In the end, you should go with your vision.  After all, it is what makes your sets worth it!

John